Various digital codeword detectors and detection schemes are known in the art. One technique involves scanning for N consecutive identical codewords. For example, if the codeword is 8 bits long, then all 8 bits of a first codeword must identically match all 8 bits of the second codeword. If successful, then the third codeword is tested for an identical match of all 8 bits, and so on up to N codewords.
Another detection technique involves scanning for N consecutive occurrences of grouped majority vote equal values for all bit-positions of the codeword. For example, a first group of five codewords is tested for each bit-position. In the first bit-position of each of the five codewords, a majority vote determines whether a one or a zero will be assigned to the first bit-position in a trial codeword, i.e., a three out of five majority vote in the first bit-positions of the five codewords determines the first bit-position value in the trial codeword. A majority vote is then taken on the values in the second bit-positions in the five codewords, which three out of five majority vote determines the value of the second bit-position in the trial codeword. If the codeword is 8 bits long, then this process continues until all 8 bit-positions have been tested and an 8 bit trial word has been generated. A new group of five more codewords is then tested in like manner to generate a second trial word. If this second trial word is identical to the first trial word, then a third group of five codewords is tested, and so on until N consecutive identical trial words have been generated.